Origin and molecular pathogenesis of ovarian high-grade serous carcinoma.

A new paradigm for the pathogenesis of ovarian cancer has recently been proposed which helps to explain persistent problems in describing the development and diverse morphology of these neoplasms. The paradigm incorporates recent advances in our understanding of the molecular pathogenesis of epithelial 'ovarian' cancer with new insights into the origin of these tumors. Correlated clinicopathologic and molecular genetic studies led to the development of a dualistic model that divides all the various histologic types of epithelial ovarian carcinomas into two broad categories designated 'type I' and 'type II'. The prototypic type I tumor is low-grade serous carcinoma and the prototypic type II tumor is high-grade serous carcinomas (HGSCs). As the serous tumors comprise ∼70% of all epithelial ovarian tumors and account for the majority of deaths, the serous tumors will be the subject of this review. There are marked differences between the low-grade and high-grade serous tumors. Briefly, the former are indolent, present in stage I (tumor confined to the ovary) and develop from well-established precursors, so-called 'atypical proliferative (borderline) tumors,' which are characterized by specific mutations, including KRAS, BRAF and ERBB2; they are relatively genetically stable. In contrast, HGSCs are aggressive, present in the advanced stage, and develop from intraepithelial carcinomas in the fallopian tube. They harbor TP53 mutations in over 95% of cases, but rarely harbor the mutations detected in the low-grade serous tumors. At the time of diagnosis they demonstrate marked chromosomal aberrations but over the course of the disease these changes remain relatively stable. Along with the recent advances in understanding the molecular pathogenesis of these tumors, studies have demonstrated that the long sought for precursor of ovarian HGSC appears to develop from an occult intraepithelial carcinoma in the fimbrial region of the fallopian tube designated 'serous tubal intraepithelial carcinoma (STIC)' and involves the ovary secondarily. Another possible mechanism for the development of ''ovarian'' HGSC is implantation of normal fimbrial epithelium on the denuded ovarian surface at the site of rupture when ovulation occurs. We speculate that this tubal epithelium can result in the formation of a cortical inclusion cyst (CICs) that can then undergo malignant transformation. Thus, serous tumors may develop from inclusion cysts, as has been previously proposed, but by a process of implantation of tubal (müllerian-type) tissue rather than by a process of metaplasia from ovarian surface epithelium (OSE, mesothelial). The dualistic model serves as a framework for studying ovarian cancer and can assist investigators in organizing this complex group of neoplasms. In conjunction with the recognition that the majority of 'ovarian' carcinomas originate outside the ovary, this model also facilitates the development of new and novel approaches to prevention, screening and treatment of this devastating disease.

Assessment of TP53 mutation using purified tissue samples of ovarian serous carcinomas reveals a higher mutation rate than previously reported and does not correlate with drug resistance.

The TP53 mutation frequency in ovarian serous carcinomas has been reported to range between 50% and 80%, but a stringent analysis of TP53 using purified epithelial samples has not yet been performed to accurately assess the mutation frequency and to correlate it with the histologic grade. The purpose of this study was to assess the TP53 mutational profile in a relatively large series of high-grade (53 primary and 18 recurrent) and 13 low-grade ovarian serous tumors using DNA isolated from affinity-purified tumor cells and to correlate it with in vitro drug resistance. All samples were affinity purified, and the tumor DNA was analyzed for TP53 mutations in exons 4-9. In vitro drug resistance assays to carboplatin, cisplatin, paclitaxel, and taxotere were performed on the same tumor samples and correlated with the TP53 mutation status. TP53 mutations were detected in 57 (80.3%) of 71 high-grade carcinomas and in one (7.8%) of 13 low-grade serous tumors (an invasive low-grade serous carcinoma). The mutations were predominantly missense mutations (59.6%). TP53 mutations were associated with high-grade serous carcinomas and recurrent disease (P < 0.0001). There was no statistically significant correlation between TP53 mutation status and drug resistance assays or clinical stage (P > 0.25). The frequency of TP53 mutations using purified tumor DNA from ovarian serous carcinomas was 80.3%, which is much higher than previously reported. Furthermore, we found that TP53 is not directly involved in the development of drug resistance in high-grade ovarian serous carcinomas.

Bovine papillomavirus type 1 monoclonal antibodies.

Bovine papillomavirus type 1 (BPV-1) and type 2 (BPV-2) are the etiologic agents of fibropapillomas in cattle. Polyclonal antisera produced against BPV-1 structural antigens are cross-reactive with BPV-2. In this study BPV-1 type-specific monoclonal antibodies were produced that were not reactive with BPV-2. These monoclonal antibodies could be used for identification of BPV-1 structural antigens in acetone-fixed, frozen sections by immunofluorescence and Formalin-fixed, paraffin-embedded sections by immunoperoxidase techniques. In addition, these antibodies could be used for identification and purification of BPV-1 virions by immune electron microscopy and immunoadsorption techniques, respectively.

Oncogenic association of specific human papillomavirus types with cervical neoplasia.

Molecular hybridization analysis of human papillomavirus (HPV) DNA from 190 cervical biopsy specimens from women in the United States, Brazil, and Peru revealed viral sequences in 2 (9%) of 23 biopsy specimens of normal mature squamous epithelium, 7 (44%) of 16 biopsy specimens of metaplastic squamous epithelia, 60 (77%) of 78 cervical intraepithelial neoplasia (CIN), 57 (89%) of 64 invasive squamous carcinomas, and 8 (89%) of 9 endocervical adenocarcinomas. HPV typing by DNA hybridization revealed HPV 6 and HPV 11 sequences in metaplastic squamous epithelia, CIN I, and CIN II, but not in CIN III lesions or invasive carcinomas. HPV 16 was detected in metaplastic epithelium and in nearly half of the invasive squamous carcinomas and adenocarcinomas. It was present in 31% of CIN lesions, increasing in frequency with the severity of CIN from 20% of CIN I to 50% of CIN III. HPV 16 showed a striking difference in geographic distribution, being detected in 36% of the carcinomas from the United States compared to 64% of the carcinomas from Brazil and Peru. HPV 18 was found in metaplastic epithelia and in 17% of carcinomas but in only 1% of CIN lesions. HPV 31 was not found in metaplastic epithelium but was present in 6% of carcinomas and in 18% of CIN lesions. In addition, a group of uncharacterized HPVs, not corresponding to any of the probes used, was found in 5% of normal and metaplastic epithelia and in 18% of CIN and 19% of invasive cancers. These results suggest that individual HPV types that infect the cervix have varying degrees of oncogenic association. HPV 6 and HPV 11 appear to have very little oncogenic association, HPV 31 has low oncogenic association, and HPV 16 and HPV 18 have high oncogenic association.

Epidemiologic evidence showing that human papillomavirus infection causes most cervical intraepithelial neoplasia.

BACKGROUND: Experimental studies have provided strong evidence that human papillomavirus (HPV) is the long-sought venereal cause of cervical neoplasia, but the epidemiologic evidence has been inconsistent. PURPOSE: Given improvements in HPV testing that have revealed a strong link between sexual activity history and cervical HPV infection, we conducted a large case-control study of HPV and cervical intraepithelial neoplasia (CIN) to evaluate whether sexual behavior and the other established risk factors for CIN influence risk primarily via HPV infection. METHODS: We studied 500 women with CIN and 500 control subjects receiving cytologic screening at Kaiser Permanente, a large prepaid health plan, in Portland, Ore. The established epidemiologic risk factors for CIN were assessed by telephone interview. We performed HPV testing of cervicovaginal lavage specimens by gene amplification using polymerase chain reaction with a consensus primer to target the L1 gene region of HPV. Unconditional logistic regression analysis was used to estimate relative risk of CIN and to adjust the epidemiologic associations for HPV test results to demonstrate whether the associations were mediated by HPV. RESULTS: The case subjects demonstrated the typical epidemiologic profile of CIN: They had more sex partners, more cigarette smoking, earlier ages at first sexual intercourse, and lower socioeconomic status. Statistical adjustment for HPV infection substantially reduced the size of each of these case-control differences. Seventy-six percent of cases could be attributed to HPV infection; the results of cytologic review suggested that the true percentage was even higher. Once HPV infection was taken into account, an association of parity with risk of CIN was observed in both HPV-negative and HPV-positive women. CONCLUSION: The data show that the great majority of all grades of CIN can be attributed to HPV infection, particularly with the cancer-associated types of HPV. IMPLICATIONS: In light of this conclusion, the investigation of the natural history of HPV has preventive as well as etiologic importance.

Cofactors with human papillomavirus in a population-based study of vulvar cancer.

BACKGROUND: Human papillomavirus (HPV) has been previously associated with vulvar cancer. In a population-based study, we examined whether exposure to HPV, cigarette smoking, or herpes simplex virus 2 (HSV2) increases the risk of this cancer. METHODS: Incident cases of in situ (n = 400) and invasive (n = 110) squamous cell vulvar cancer diagnosed among women living in the Seattle area from 1980 through 1994 were identified. Serum samples were analyzed for antibodies against specific HPV types and HSV2. HPV DNA in tumor tissue was detected by means of the polymerase chain reaction. In most analyses, case subjects were compared with population-based control subjects (n = 1403). Relative risks of developing vulvar cancer were estimated by use of adjusted odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Increased risks of in situ or invasive vulvar cancer were associated with HPV16 seropositivity (ORs = 3.6 [95% CI = 2.6-4.8] and 2.8 [95% CI = 1.7-4.7], respectively), current cigarette smoking (ORs = 6.4 [95% CI = 4.4-9.3] and 3.0 [95% CI = 1.7-5.3], respectively), and HSV2 seropositivity (ORs = 1.9 [95% CI = 1.4-2.6] and 1.5 [95% CI = 0.9-2.6], respectively). When the analysis was restricted to HPV16 DNA-positive tumors (in situ or invasive), the OR associated with HPV16 seropositivity was 4.5 (95% CI = 3.0-6.8). The OR for vulvar cancer was 18.8 (95% CI = 11.9-29.8) among current smokers who were HPV16 seropositive in comparison with never smokers who were HPV16 seronegative. CONCLUSIONS: Current smoking, infection with HPV16, and infection with HSV2 are risk factors for vulvar cancer. Risk appears particularly strong among women who are both current smokers and HPV16 seropositive.

Detection of human papillomavirus DNA in cytologically normal women and subsequent cervical squamous intraepithelial lesions.

BACKGROUND: Human papillomavirus (HPV) infection has been strongly associated with cervical carcinoma and its cytologic precursors, squamous intraepithelial lesions (SIL). We investigated the risk of SIL prospectively following polymerase chain reaction (PCR)-based DNA testing for a wide range of genital HPV types in a cohort of initially cytologically normal women, to clarify the role of HPV in the etiology of SIL. METHODS: Starting in April 1989, 17,654 women who were receiving routine cytologic screening at Kaiser Permanente (Portland, OR) were followed for the development of incident SIL. During follow-up, 380 incident case patients and 1037 matched control subjects were eligible for this nested case-control study. Cervical lavages collected at enrollment and, later, at the time of case diagnosis (or the corresponding time for selection of control subjects) were tested for HPV DNA using a PCR-based method. The data were analyzed as contingency tables with two-sided P values or, for multivariable analyses, using odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: In comparison with initially HPV-negative women, women who tested positive for HPV DNA at enrollment were 3.8 times (95% CI = 2.6-5.5) more likely to have low-grade SIL subsequently diagnosed for the first time during follow-up and 12.7 times more likely (95% CI = 6.2-25.9) to develop high-grade SIL. At the time of diagnosis, the cross-sectional association of HPV DNA and SIL was extremely strong (OR = 44.4 and 95% CI = 24.2-81.5 for low-grade SIL and OR = 67.1 and 95% CI = 19.3-233.7 for high-grade SIL). HPV16 was the virus type most predictive of SIL, even low-grade SIL. CONCLUSIONS: These findings are consistent with the hypothesis that HPV infection is the primary cause of cervical neoplasia. Furthermore, they support HPV vaccine research to prevent cervical cancer and efforts to develop HPV DNA diagnostic tests.

Oral contraceptive use, human papillomavirus infection, and risk of early cytological abnormalities of the cervix.

Oral contraceptive (OC) use was examined as a risk factor for cytological abnormalities of the cervix among 1964 women receiving Papanicolaou smears at three hospitals in the Washington, D.C., area. A single pathologist classified cytological results from all women as normal (n = 1423), atypia (n = 314), low grade squamous intraepithelial lesion (SIL; n = 208), or high grade SIL (n = 19). Women in each of the three abnormal groups were compared to women with normal cytological diagnoses. A subset of 579 patients, including most of the women with low or high grade SIL and a matched group of controls, was tested for human papillomavirus (HPV) by type-specific Southern blot hybridization to examine the effects of OC use while taking into account the effects of HPV infection. OC use was found to be unrelated to risk of atypia or low grade SIL but was associated with an elevated risk of high grade SIL that increased with longer duration of use (relative risk = 4.6, 95% confidence interval = 1.1-18.1 for greater than or equal to 5 years of use). HPV infection was associated, as expected, with risk of low and high grade SIL but not with atypia. Taking the HPV results into consideration did not alter the OC findings. There was no evidence that OC use synergistically increased the risk of cervical neoplasia among HPV-infected women, although small numbers prevented a reliable evaluation for high grade SIL. OC use did appear to increase the detection of HPV types 16/18, but the etiological importance of this finding is unclear.

PTEN mutations and microsatellite instability in complex atypical hyperplasia, a precursor lesion to uterine endometrioid carcinoma.

The two most common types of genetic alterations yet identified in uterine endometrioid carcinoma (UEC) are PTEN mutations and microsatellite instability (MI). Furthermore, MI-positive UECs (defined as tumors with detectable alterations at two or more different microsatellite loci) are significantly more likely to contain PTEN mutations than are MI-negative UECs. To determine whether PTEN inactivation is a relatively early event in endometrial tumorigenesis, we evaluated complex atypical hyperplasia (CAH), the direct precursor to UEC, for the presence of PTEN mutations. Mutations were present in 3 of 11 (27%) CAHs with synchronous UEC and in 4 of 18 (22%) CAHs that were not associated with invasive carcinoma. One case with synchronous CAH and UEC contained a germ-line PTEN mutation. In addition, we evaluated the same series of CAHs for MI. We identified four MI-positive CAHs with synchronous UEC but did not detect the MI phenotype in any CAHs without associated invasive carcinoma. A PTEN-mutant (germ-line mutation) MI-negative CAH was synchronous with a PTEN-mutant MI-positive UEC. These results suggest that mutation of PTEN can be an early event in the pathogenesis of UEC and may precede the development of the MI phenotype in a subset of cases.

Biochemical epidemiology of cervical neoplasia: measuring cigarette smoke constituents in the cervix.

In preparation for an epidemiological investigation of cigarette smoking and cervical neoplasia, we studied methods of measuring cervical exposure to tobacco smoke. The measurement of cotinine in cervical flushes by radioimmunoassay proved to be highly accurate in distinguishing smokers from nonsmokers, achieving 100% sensitivity and 97% specificity. In most subjects, quantitative levels of cervical cotinine and nicotine mirrored recent smoking intensity. Some of the apparent exceptions may have resulted from metabolic/secretory traits of the subjects. If so, the biochemical measurement of smoke constituents in the cervix might prove more valuable for epidemiological studies of cervical neoplasia than data on current smoking behavior collected by interview.

Preliminary analysis of the behavior of stage I ovarian serous tumors of low malignant potential: a Gynecologic Oncology Group study.

PURPOSE: From December 1983 through February 1992, a prospective study designed to determine the clinical course of patients with ovarian tumors of low malignant potential (LMP) was conducted by the Gynecologic Oncology Group (GOG). MATERIALS AND METHODS: This protocol was developed to evaluate the following (1) the biologic behavior of ovarian LMP tumors, (2) the effectiveness of melphalan chemotherapy in patients with clinically detectable residual disease after surgical staging and in patients whose tumors progress or recur after surgical therapy, and (3) the response rate to cisplatin in those who failed to respond to melphalan therapy. The study group consisted of 146 assessable patients with stage I serous LMP tumors. All of these women had the affected ovary (or ovaries) removed, and a complete staging operation was performed in each case. While 123 patients had a total abdominal hysterectomy (TAH) and bilateral salpingo-oophorectomy (BSO), 21 retained the uterus and one normal-appearing ovary and fallopian tube. No adjuvant chemotherapy or radiation therapy was administered to any patients in the stage I study group. RESULTS: The median follow-up time was 42.4 months (range, 1.6 to 108). Thus far, no patient with a stage I ovarian serous LMP tumor has developed recurrent disease. CONCLUSION: Stage I ovarian serous LMP tumors rarely, if ever, recur. Limited resection, after meticulous surgical exploration, is adequate therapy for women of reproductive age.

Targeting human papillomavirus type 16 E7 to the endosomal/lysosomal compartment enhances the antitumor immunity of DNA vaccines against murine human papillomavirus type 16 E7-expressing tumors.

DNA vaccination is an attractive approach for tumor immunotherapy because of its stability and simplicity of delivery. Advances demonstrate that helper T cell responses play a critical role in initiating immune responses. The aim of the current study is to test whether targeting HPV-16 E7 to the endosomal/lysosomal compartment can enhance the potency of DNA vaccines. We linked the lysosome-associated membrane protein 1 (LAMP-1) to HPV-E7 to construct a chimeric DNA, Sig/E7/LAMP-1 DNA. For in vivo tumor prevention experiments, mice were vaccinated with E7 DNA or Sig/E7/LAMP-1 DNA via gene gun, followed by tumor challenge. For in vivo tumor regression experiments, mice were first challenged with tumor cells and then vaccinated with E7-DNA or Sig/E7/LAMP-1 DNA. Intracellular cytokine staining with flow cytometry analysis, cytotoxic T lymphocyte (CTL) assays, enzyme-linked immunoabsorbent assay (ELISA), and enzyme-linked immunospot (ELISPOT) assays were used for in vitro E7-specific immunological studies. In both tumor prevention and tumor regression assays, Sig/E7/LAMP-1 DNA generated greater antitumor immunity than did wild-type E7 DNA. In addition, mice vaccinated with Sig/E7/LAMP-1 DNA had greater numbers of E7-specific CD4+ helper T cells, higher E7-specific CTL activity, and greater numbers of CD8+ T cell precursors than did mice vaccinated with Sig/E7 or wild-type E7 DNA. Sig/E7 generated a stronger E7-specific antibody response than did Sig/E7/LAMP-1 or wild-type E7 DNA. Our results indicate that linkage of the antigen gene to an endosomal/lysosomal targeting signal may greatly enhance the potency of DNA vaccines.

Adrenocorticotropin-dependent virilizing paraovarian tumors in Nelson's syndrome.

A 35-yr-old woman with Nelson's syndrome presented with amenorrhea and virilization. Serum testosterone (T) concentration was 605 ng/dl and fell to 33 ng/dl when dexamethasone was administered. The MCR of T fell from 1383 to 991 liters/day and the T production rate decreased by 96%. With administration of synthetic ACTH, T concentration rose to 338 ng/dl. Plasma ACTH concentration paralleled T during repeated suppression testing, suggesting that T secretion was dependent on ACTH hypersecretion. Preoperative and intraoperative ovarian vein catheterization suggested that the predominant source of androgen production was from the right ovarian vein. Laporatomy revealed multiple paraovarian tumors in the right mesosalpinyx and mesovarium. Incubation of tumor slices and ovarian tissue with [3H]pregnenolone and [14C]17-hydroxyprogesterone demonstrated conversion of both precursors to T by the tumor and confirmed that the tumors were the source of androgen excess. The microscopic appearance of the tumors closely resembled the morphology of testicular and paratesticular tumors of men with congenital adrenal hyperplasia and Nelson's syndrome. The analogous dependency of the tumors on ACTH hypersecretion in men with paratesticular tumors and in this woman with paraovarian tumors suggests that the tumors may arise in both males and females from a common steroid-secreting cell of adrenogenital origin.

Histological characteristics of breast carcinoma in blacks and whites.

Tumor characteristics of 963 newly diagnosed invasive breast cancer cases from the population-based Black/White Cancer Survival Study were evaluated. Representative slides of the tumors were requested from all participating hospitals of three metropolitan areas and reviewed by one expert pathologist, blinded in regard to the age and race of patients. Nine tumor characteristics were evaluated for black and white patients. After adjusting for age, stage, and metropolitan area, blacks were significantly more likely to have high grade nuclear atypia [odds ratio (OR) = 1.97, 95% confidence interval (CI) = 1.27-3.04]; high mitotic activity (OR = 2.05, 95% CI = 1.34-3.14), grade 3 tumors (OR = 1.58, 95% CI = 1.02-2.45), and more necrosis (OR = 1.51, 95% CI = 1.16-1.98); and less likely to have well defined tubular formation (OR = 0.57, 95% CI = 0.42-0.77), marked fibrosis (OR = 0.65, 95% CI = 0.45-0.94), and positive estrogen receptor status (OR = 0.78, 95% CI = 0.58-1.05). These black/white differences remained after controlling for socioeconomic status (SES), body mass index, use of alcohol and tobacco, reproductive experience, and health care access and utilization. No significant racial differences were found for blood vessel invasion and lymphatic invasion. Although white women of high SES had more favorable tumors than those of low SES, the same pattern was not observed for blacks. High SES black women had statistically nonsignificant elevated ORs of a high mitotic index and tumor grade. These racial differences in tumor biology may have etiological and clinical implications.

Human leukocyte antigen class I/II alleles and development of human papillomavirus-related cervical neoplasia: results from a case-control study conducted in the United States.

The host immune response to human papillomaviruses (HPVs) is believed to be an important determinant of progression of HPV-associated cervical neoplasia. Human leukocyte antigens (HLAs) are important in the presentation of foreign antigens to the immune system. Previous studies have suggested a possible association between HLA and cervical neoplasia, but the specific alleles found to be associated with disease have varied between studies. To further evaluate this issue, we conducted a nested case-control study within a 24,000-woman cohort study in the United States. A total of 711 women were selected for the study: 141 women diagnosed with high-grade squamous intraepithelial lesions (HSILs) of the cervix; 202 women diagnosed with low-grade SILs (LSILs); 166 women with no history of cervical neoplasia, but evidence of HPV-16 infection; and 202 women with no history of cervical abnormalities and who were HPV negative during follow-up as part of our cohort. Cervicovaginal lavage samples collected from participants were used for HPV testing by L1 consensus primer PCR and the Hybrid Capture tube test methods. DNA extracted from these same lavage samples were used for PCR-based HLA genotyping. Our results suggest a positive association between HLA B7 and HLA DQB1*0302 and disease. A negative association with disease was observed for HLA DRB1*1501-DQB1*0602 and DRB1*13. Associations were strongest when analyses were restricted to HPV-16-positive cases as follows. Compared with women who were cytologically normal and HPV negative, HLA B7 was associated with a 1.5-fold increased risk of HPV/LSIL [95% confidence interval (CI) = 0.95-2.5] and a 2.5-fold increased risk of HSIL (95% CI = 1.2-5.1). HLA DQB1*0302 was associated with a 1.5-fold increased risk of HPV/LSIL (95% CI = 0.94-2.4) and a 1.7-fold increased risk of HSIL (95% CI = 0.84-3.5). HLA DRB1*1501-DQB1*0602 was associated with a decreased risk of HSIL [relative risk (RR) = 0.21; 95% CI = 0.07-0.62]. HLA DRB1*13 was associated with a decreased risk of HPV/LSIL (RR = 0.78; 95% CI = 0.51-1.2) and HSIL (RR = 0.63; 95% CI = 0.30-1.3). Individuals who were either homozygous for DQB1*0302 or carriers of both B7 and DQB1*0302 were found to be at highest risk of disease (RR = 4.5, 95% CI = 1.5-14 for HPV/LSIL; and RR = 9.0, 95% CI = 2.4-34 for HSIL). No synergistic effect was observed for the alleles found to be associated with reduced risk of cervical neoplasia. Our findings support previous studies that have found HLA B7 and DQB1*0302 to be positively associated with cervical neoplasia and are consistent with those that have suggested that DRB1*13 is negatively associated with disease, but do not confirm previous assertions that DRB1*1501-DQB1*0602 increases the risk of cervical disease.

Analysis of histopathological features of endometrioid uterine carcinomas and epidemiologic risk factors.

A large case-control study was performed to determine whether risk factors for endometrioid carcinoma, the most common type of endometrial cancer, vary according to the histological features of the tumor. Study subjects consisted of 328 women with newly diagnosed endometrioid adenocarcinoma and 320 population-based control subjects. Variables studied included age at menarche, menopausal estrogen use, weight, parity, cigarette smoking, and oral contraceptive use. The risk factor profile for endometrioid carcinomas with and without squamous differentiation was very similar. No striking differences in risk factors were observed between endometrioid cancers with and without adjacent endometrial hyperplasia. Finally, none of the risk factors varied substantially between early-stage and late-stage tumors or low-grade and high-grade tumors. In summary, this study indicates that risk factors for endometrioid carcinomas are not related to the morphological features of the tumor.

Evidence for at least two distinct groups of humoral immune reactions to papillomavirus antigens in women with squamous intraepithelial lesions.

Serological markers of squamous intraepithelial lesions (SILs), the precursors of cervical cancer, have not been studied extensively. To screen for antibody responses that might be associated with SILs, we measured IgG and/or IgA to nine antigens based on papillomaviruses, the infectious cause of SIL and cervical cancer, using an ELISA format. Cases were 59 women with low grade SIL (LSIL) and 38 with high grade SIL (HSIL). Controls were 50 women chosen to minimize the possibility that they ever had SILs [individuals who had no history of SIL and repeatedly tested negative for cervical human papillomavirus (HPV) DNA], frequency age-matched to cases. The data showed that five antibodies had strong positive associations with SILs and that one was inversely related to SILs. By studying these antibodies in pairs, furthermore, we found that case-control differences were enhanced. In particular, the combination of IgG to an epitope in the E6 protein of HPV 16 (E6:10) and IgA to HPV 16 virus-like particles (VLPs) was detected in 53% of LSILs and 65% of HSILs but only 9% of controls. These same responses were both negative in just 6% of LSILs and zero HSILs, compared to 59% of controls. Notably, E6:10 IgG and HPV 16 VLP IgA were not correlated with each other, and the other antibody responses positively associated with SILs could be broken into two groups: those correlated with E610 IgG and those correlated with HPV 16 VLP IgA. Overall, the data suggest that several papillomavirus antibodies may be strongly related to SILs, and that they can be divided into at least two independent groups of humoral immune reactions.

Immune activation in cervical neoplasia: cross-sectional association between plasma soluble interleukin 2 receptor levels and disease.

In a previous study (Tsukui et al., Cancer Res., 56: 3967-3974, 1996), we observed an inverse association between degree of cervical neoplasia and interleukin (IL) 2 production by peripheral blood mononuclear cells in response to human papillomavirus (HPV) 16 E6 and E7 peptides in vitro. This suggested that a Th1-mediated cellular immune response might be important in host immunological control of HPV infection and that a lack of such a response might predispose to progression of cervical disease. To follow up on these findings, we have conducted a cross-sectional study of women with various degrees of cervical neoplasia to investigate the association between overall immune activation and cervical disease. A total of 235 women were recruited into our study; 120 of these women were participants in our previous study in which IL-2 production in response to HPV-16-specific peptides was measured. The study population included 34 women with invasive cancer, 62 women with high-grade squamous intraepithelial lesions (HSILs), and 105 women with low-grade squamous intraepithelial lesions (LSILs). In addition, 34 cytologically normal women with no past history of squamous intraepithelial lesions despite confirmed HPV-16 infection in the 5 years preceding the study were selected as controls. As our measure of overall immune activation, serum samples obtained from study participants were tested for soluble IL-2 receptor (sIL-2R) level using an ELISA method. The mean sIL-2R levels were found to increase with increasing disease severity (Ptrend = 0.0002). Among cytologically normal, HPV-exposed women, the mean receptor level in serum was 465.8 units/ml compared to 467.6 units/ml among LSIL subjects, 514.9 units/ml among HSIL subjects, and 695.5 units/ml among women with invasive cervical cancer. Similarly, the proportion of women with elevated sIL-2R levels (defined as > or = 450 units/ml) increased with increasing disease severity from 35.2% among normal study subjects to 70.6% among cancer patients (Ptrend = 0.003). Among the subgroup of subjects for whom in vitro IL-2 production in response to HPV-16-specific peptides was measured, we examined the association between in vitro IL-2 production and serum levels of sIL-2R. sIL-2R levels were higher, on average, among those women who were positive in our IL-2 production assay compared to those who were negative, but the differences did not reach statistical significance (P > 0.05). We also observed a trend of increasing sIL-2R level with increasing disease severity both in women who were positive and in women who were negative for our IL-2 production assay, but the trend was only significant among those who were negative for IL-2 production (Ptrend = 0.01). Results from our studies suggest that although the immune system of women with cervical neoplasia is nonspecifically activated as disease severity increases, the ability of those women with HSILs or cancer to mount a Th1-mediated immune response to HPV peptides appears to decrease compared to women with LSILs or normal women infected with HPV. Increased overall activation along with decreased Th1 immune response among women with increasing cervical disease severity might be explained by an increased Th2-mediated immune response, a response that we hypothesize is ineffective in controlling the viral infection and its early cytological manifestations. Future studies should directly assess Th2-mediated responses to confirm this hypothesis. Also, future efforts should be aimed at determining whether the associations observed are causally related to disease progression or an effect of the disease.

Epithelioid trophoblastic tumor: a neoplasm distinct from choriocarcinoma and placental site trophoblastic tumor simulating carcinoma.

This report describes the clinicopathologic and immunohistochemical features of 14 cases of epithelioid trophoblastic tumor (ETT), a distinctive but rare gestational trophoblastic tumor. The patients with this neoplasm were in the reproductive age group and presented with abnormal vaginal bleeding. Although diagnosis was usually associated with a gestational event, the latter was sometimes remote. Two of the 14 patients presented with extrauterine ETT without evidence of prior gestational trophoblastic disease in the uterus. Serum human chorionic gonadotropin levels were elevated in eight of nine patients in whom this information was available. In the uterus, ETT presented as a discrete, hemorrhagic, solid and cystic lesion that was located either in the fundus, lower uterine segment, or endocervix. Microscopically, the tumor was composed of a relatively uniform population of mononucleate intermediate trophoblastic cells forming nests and solid masses. The cells resemble the trophoblastic cells in the chorion laeve, and we have therefore designated them "chorionic-type intermediate trophoblast." Typically, islands of trophoblastic cells were surrounded by extensive necrosis and were associated with a hyaline-like matrix creating a "geographic" pattern that is quite characteristic of this lesion. The mean mitotic count was two mitoses per 10 high-power fields, and the average Ki-67 nuclear labeling index was 18%. Immunohistochemically, all cases were diffusely positive for inhibin-alpha, cytokeratin (AE1/AE3), epithelial membrane antigen, E-cadherin, prolyl 4-hydroxylase, and epidermal growth factor receptor but were only focally immunoreactive for human placental lactogen, human chorionic gonadotropin, PlAP, and Mel-CAM. The monomorphic growth pattern of ETT resembles placental site trophoblastic tumor to a much greater degree than choriocarcinoma which is characterized by a dimorphic population of trophoblast. In contrast to placental site trophoblastic tumor, the cells of ETT are smaller and display less nuclear pleomorphism. In addition, ETT grows in a nodular fashion compared with the infiltrative pattern of placental site trophoblastic tumor. In some of the cases, the trophoblastic cells in ETT replaced the endocervical surface epithelium, giving the appearance that the tumor was derived from the cervix. Moreover, because the associated hyaline-like material in ETT resembles keratin, the tumor can be misinterpreted as a keratinizing squamous cell carcinoma of the cervix. Ten patients underwent total hysterectomy and two had an endometrial curettage only. The two patients who presented with extrauterine ETT underwent small bowel resection and lung resection. Two of 12 patients with ETT in the uterus developed metastasis in the lungs and bone. One of these patients is alive with disease at 43 months and one patient was lost to follow-up after 2 months. One of the two patients who had extrauterine disease died of widespread tumor 36 months after diagnosis. The remainder of the patients are alive and well from 1 to 120 months. In summary, ETT is a rare trophoblastic tumor that simulates carcinoma and can behave in a malignant fashion. It appears to be less aggressive than choriocarcinoma, more closely resembling the behavior of placental site trophoblastic tumor. Based on the morphologic and immunohistochemical features, it appears that ETT develops from neoplastic transformation of chorionic-type intermediate trophoblast.

A clinicopathologic analysis of atypical proliferative (borderline) tumors and well-differentiated endometrioid adenocarcinomas of the ovary.

Atypical proliferative (borderline) endometrioid tumors (APTs) and well-differentiated endometrioid carcinomas of the ovary constitute a spectrum of morphologically diverse proliferative tumors. There is currently no agreement on the criteria for distinguishing them. We report the clinicopathologic features of 56 proliferative endometrioid tumors focusing on the criteria for invasion, the clinical significance of microinvasion and cytologic atypia, and prognosis. Endometriomas, adenofibromas, adenosarcomas and moderately to poorly differentiated carcinomas were excluded, as were patients with concurrent endometrioid carcinoma of the endometrium. The tumors were classified as atypical proliferative tumor (APT) (33 tumors), APT with intraepithelial carcinoma (high-grade cytology in a tumor lacking stromal invasion) (three tumors), APT with microinvasion (invasion <5 mm) (five tumors), and invasive carcinoma (invasion > or = 5 mm) ( 15 tumors). All tumors were confined to the ovary (stage I). In 50 patients, the tumor involved one ovary, and in three patients, the tumors were bilateral. The predominant growth pattern was adenofibromatous in 29 tumors and glandular or papillary in 27 tumors. In 8 (24%) of 41 APTs, areas of benign adenofibroma were identified, and in 13 (87%) of 15 carcinomas, areas of associated APT were identified. Stromal invasion was manifested by confluent glandular growth in all 15 invasive carcinomas and all tumors with microinvasion. Destructive infiltrative growth was also present in 2 (13%) of 15 carcinomas. Confluent glandular growth was the most common manifestation of stromal invasion and therefore served as the best criterion for the diagnosis of carcinoma. Squamous differentiation was observed in 24 tumors, and mucinous differentiation was seen in 20 tumors and was most often seen in APTs. Endometriosis was present in 14 patients with APTs and one patient with carcinoma. Four patients had hyperplasia or atypical hyperplasia of the endometrium. One patient with an APT had a concurrent peritoneal serous neoplasm. Twenty-one patients had available clinical follow-up. Twenty (95%) of 21 patients, including six with invasive carcinoma, two with microinvasion, one with intraepithelial carcinoma, and 11 with APT were alive with no evidence of disease with a mean follow-up of 47 months. One patient with carcinoma had recurrent tumor after 46 months and was alive 40 months after resection of the recurrent tumor. In this large series of proliferative endometrioid tumors, all were stage I and only one patient had a recurrence. Most carcinomas contained evidence of a precursor APT, and in some APTs, an associated benign adenofibroma was identified. Microinvasion or intraepithelial carcinoma occurred in 19% of APTs. This finding likely reflects the various stages of endometrioid carcinogenesis in the ovary. For clinical management, we suggest that these tumors be divided into two categories-APTs and well-differentiated carcinoma-because based on the available data, cytologic atypia and microinvasion appear not to affect the prognosis.